question about a bit of popping from the exhaust

[Zedyone_kenobi]

I have had my Z therapy carbs on my car for a while and quite frankly they are wonderful. I have had this issue that I wonder if people can shed some light on.

If I take my car out for a romp, during the first 15 minutes of driving when I rev it to 4500 slowly it pops at times through the exhaust. But if I step on it and quickly rev it, meaning I do not dwell at 4500 rpm it revs just fine and pulls hard to 6500. Now, if I keep driving around for an extended period of time this occasional popping goes completely away and I can rev smoothly through 4500 with no issues at all. I can even dwell at 4500 rpm with no issues.

I wonder at times, if this is due to the manifold not being warmed up and the fuel is not making it to the intake completely atomized. I do not remember this happening in the heat of summer.

Just curious. It really is no big deal as the car drives beautifully.

[Diseazd]

Mine did that a couple weeks ago. It was leaking between the down pipe and the manifold (the two hole gasket that costs about $4.50). I bought a tube of muffler seal, put two gaskets together along with muffler seal between the gaskets and on the downpipe and manifold surfaces, bolted her up.....let it harden for 5 hours and now there no pop back. You can see if this is the problem by putting her up on a lift while running and hold your hand around the connection. If it's leaking, you'll probably be able to feel the leak.....I could. Guy

[ChrisZ]

What about under decelleration, will it also pop then?

As Guy said, unburned fuel can be ignited if there is a leak in the exhaust, i'm thinking dampener oil, what are you using.

Chris

[Zedyone_kenobi]

real deal SU oil!

[Zedyone_kenobi]

I do get some blurble upon deceleration, but this definitely not the same thing.